# cd
alias ..='cd ../'
alias ...='cd ../..'

# system update
alias sys.update='sudo apt-get update'
alias sys.upgrade='sudo apt-get upgrade'
alias sys.dist-update='sudo apt-get dist-upgrade'
alias sys.autoremove='sudo apt-get autoremove'
alias sys.autoclean='sudo apt-get autoclean'

# extract file
extract() {
    if [ -f $1 ] ; then
        case $1 in
            *.tar.bz2)  tar xjf $1      ;;
            *.tar.gz)   tar xzf $1      ;;
            *.tar.xz)   tar xpf $1      ;;
            *.bz2)      bunzip2 $1      ;;
            *.rar)      unrar e $1      ;;
            *.gz)       gunzip $1       ;;
            *.tar)      tar xf $1       ;;
            *.tbz2)     tar xjf $1      ;;
            *.tgz)      tar xzf $1      ;;
            *.zip)      unzip $1        ;;
            *.Z)        uncompress $1   ;;
            *.7z)       7z x $1         ;;
            *)      echo "'$1' cannot be extracted via extract()" ;;
        esac
    else
        echo "'$1' is not a valid file"
    fi
}
